Language Reactor

Language Reactor is a Chrome extension for learning from real video content. It is best if you like studying Vietnamese through Netflix shows or YouTube videos instead of following a textbook-style course.

On Netflix, it overlays dual subtitles and adds a pop-up dictionary so you can click words and understand lines without constantly pausing to search elsewhere. It also gives you tighter playback controls to replay lines and study timing more closely.

On YouTube, you can use the same idea with subtitles, which makes it handy for learning from channels you already watch. You can also import text from books or websites inside Language Reactor for machine translation and text-to-speech practice.

It is strong for listening plus reading support and quick vocabulary lookups, but it does not teach a structured Vietnamese curriculum or speaking practice. Some study features are gated behind Pro, and it works as a desktop Chrome add-on rather than a standalone mobile app. You can start on the Language Reactor website and install it from the Chrome Web Store.